1 Title: Anti-secretory effect of hydrogen sulfide on gastric acid secretion and the involvement of nitric oxide Running title: The Anti-secretory and antacid properties of H 2 S Authors: * Seyyed Ali Mard 1 , Hasan Askari 2 , Niloofar Neisi 3 , Ali Veisi 1 1 Research institute for infectious diseases of digestive system, Physiology Research Center (PRC) and Dept. of Physiology, the School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran 2 Research institute for infectious diseases of digestive system, the School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz and Dept. of physiology, the School of Medicine, Tehran University of Medical Sciences, Tehran, Iran 3 Research institute for infectious diseases of digestive system and Dept. of Virology, the School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran * Corresponding author: Seyyed Ali Mard, Research institute for infectious diseases of digestive system, Physiology Research Center (PRC) and Dept. of Physiology, the School of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran Email: alimard77@gmail.com ; mard-sa@ajums.ac.ir Tel:+986113201490 , +989166118532 Fax: +986113332036